Discovery [1] | |
---|---|
Discovered by | C. Shoemaker |
Discovery site | Palomar Obs. |
Discovery date | 5 May 1986 |
Designations | |
(4765) Wasserburg | |
Named after | Gerald J. Wasserburg (American geologist) [2] |
1986 JN1 ·1983 EA1 1986 LF | |
main-belt (inner) [1] · Hungaria [3] [4] | |
Orbital characteristics [1] | |
Epoch 4 September 2017 (JD 2458000.5) | |
Uncertainty parameter 0 | |
Observation arc | 33.15 yr (12,108 days) |
Aphelion | 2.0621 AU |
Perihelion | 1.8289 AU |
1.9455 AU | |
Eccentricity | 0.0599 |
2.71 yr (991 days) | |
237.52° | |
0° 21m 47.52s / day | |
Inclination | 23.710° |
76.546° | |
108.33° | |
Known satellites | 1 (suspected) [5] [6] |
Physical characteristics | |
1.777±0.485 km [7] [8] 3.82 km (calculated) [4] | |
3.6231±0.0005 h [5] 3.625±0.001 h [9] 3.62532±0.00002 h [lower-alpha 1] 3.626±0.005 h [lower-alpha 2] 3.6260±0.0005 h [10] 3.6280±0.0005 h [11] 3.664±0.003 h [12] 3.67±0.02 h (dated) [13] | |
0.4 (assumed) [4] 1.000±0.087 [7] [8] | |
E [4] B–V = 0.852±0.043 [14] V–R = 0.456±0.023 [14] V–I = 0.813±0.040 [14] | |
13.7 [1] [4] ·14.1 [7] | |
4765 Wasserburg (prov. designation: 1986 JN1) is a bright Hungaria asteroid, suspected binary system and asteroid pair from the innermost regions of the asteroid belt, approximately 3 kilometers (1.9 miles) in diameter. It was discovered on 5 May 1986, by American astronomer Carolyn Shoemaker at Palomar Observatory, and later named after geologist Gerald J. Wasserburg. [2] [3]
Wasserburg is a bright member of the Hungaria family, which form the innermost dense concentration of asteroids in the Solar System. It orbits the Sun in the inner main-belt at a distance of 1.8–2.1 AU once every 2 years and 9 months (991 days). Its orbit has an eccentricity of 0.06 and an inclination of 24° with respect to the ecliptic. [1] It was first identified as 1983 EA1 at Palomar in 1983, extending the body's observation arc by 3 years prior to its official discovery observation. [3]
Wasserburg forms an asteroid pair with (350716) 2001 XO105, and was part of Petr Pravec's sample study Formation of asteroid pairs by rotational fission, published in the journal Nature. [4] [10]
This minor planet was named after American Gerald J. Wasserburg (1927–2016), who was a professor of geology and geophysics at Caltech in California. He was a pioneer of radiometric dating methods used in isotope geochemistry and was prominent for his accurate age determination measurements of Moon rocks, which were instrumental for reconstructing the origin of the Moon and for the hypothesis of the Late Heavy Bombardment. [2] Wasserburg also carried out isotopic analyses of meteorites, developed a time scale for the formation and evolution of the Solar System, and contributed to the theory of nucleosynthesis. [2] The official naming citation was published on 27 June 1991 ( M.P.C. 18464). [15]
According to preliminary results from the survey carried out by NASA's Wide-field Infrared Survey Explorer (WISE) with its subsequent NEOWISE mission, Wasserburg measures 1.777 kilometers in diameter and its surface has an outstandingly high albedo of 1.000, [7] [8] while the Collaborative Asteroid Lightcurve Link assumes it to be an E-type asteroid, with albedo of 0.40 – derived from 434 Hungaria the family's namesake and most prominent member – and calculates a larger diameter of 3.82 kilometers with an absolute magnitude of 13.7. [4]
Between 2006 and 2014, several rotational lightcurves of Wasserburg were obtained from photometric observations by astronomers Brian Warner at his Palmer Divide Observatory ( 716 ), Petr Pravec at Ondřejov Observatory, and Julian Oey at Blue Mountains Observatory ( E19 ). Best rated lightcurve analysis gave a well-defined rotation period between 3.6231 and 3.6280 hours with a brightness variation between 0.07 and 0.60 magnitude ( U=3/3/3/3- ). [5] [9] [10] [11] [lower-alpha 1] [lower-alpha 2] [lower-alpha 3] Due to the changing amplitude, Wasserburg is likely one of the more elongatedly shaped primary asteroids of all known smaller binaries with an diameter of less than 10 kilometers. [5]
After being already recognized as an asteroid pair, American astronomer Brian Warner observed faint mutual eclipsing and occultation events in April 2013. After repeated lightcurve subtraction, he was able to show that Wasserburg is likely a binary system with a minor-planet moon orbiting it every 15.97 hours. Assuming a depth of 0.03 magnitude, he estimated a secondary-to-primary mean-diameter ratio of 0.16±0.02. [5] The Johnston's archive derives a diameter of 280±80 meters for the satellite, based on the primary diameter given by WISE. [6] A semi-major axis of 2.9 kilometers is also estimated for the moons orbit. [6] However, photometric observations taken in 2015, could not detect the presence of a satellite and Wasserburg remains only a suspected binary. [12]
1509 Esclangona, provisional designation 1938 YG, is a rare-type Hungaria asteroid and binary system from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. It is named after French astronomer Ernest Esclangon.
2001 Einstein is a bright Hungaria asteroid from the innermost region of the asteroid belt. It was discovered by Swiss astronomer Paul Wild at Zimmerwald Observatory near Bern, Switzerland, on 5 March 1973. The X-type asteroid (Xe) has a rotation period of 5.5 hours and measures approximately 5 kilometers in diameter. It is named after physicist Albert Einstein (1879–1955).
3043 San Diego, provisional designation 1982 SA, is a stony Hungaria asteroid and slow rotator from the inner regions of the asteroid belt, approximately 4.7 kilometers in diameter.
1025 Riema, provisional designation 1923 NX, is a bright Hungaria asteroid from the innermost regions of the asteroid belt, approximately 5 kilometers in diameter. It was discovered on 12 August 1923, by German astronomer Karl Reinmuth at the Heidelberg Observatory in southwest Germany. The asteroid was named after ARI astronomer Johannes Riem.
3309 Brorfelde, provisional designation 1982 BH, is a nearly spheroidal, binary Hungaria asteroid from the inner regions of the asteroid belt, approximately 4 kilometers in diameter. It was discovered on 28 January 1982, by Danish astronomers Kaare Jensen and Karl Augustesen at the Brorfelde Observatory near Holbæk, Denmark. It was named for the discovering observatory and the village where it is located.
4674 Pauling, provisional designation 1989 JC, is a spheroidal binary Hungaria asteroid from the innermost regions of the asteroid belt, approximately 4.5 kilometers in diameter. It was discovered by American astronomer Eleanor Helin at the U.S. Palomar Observatory, California, on 2 May 1989, and named after the American chemist and Nobel laureate Linus Pauling.
1103 Sequoia is a bright Hungaria asteroid from the innermost region of the asteroid belt, approximately 7 kilometers in diameter. It was discovered on 9 November 1928, by German astronomer Walter Baade at the Bergedorf Observatory in Hamburg, Germany, who named it after the Sequoia National Park located in California.
1919 Clemence, provisional designation 1971 SA, is a bright Hungaria asteroid and suspected tumbler from the inner regions of the asteroid belt, approximately 4 kilometers in diameter. It was discovered on 16 September 1971, by American astronomer James Gibson together with Argentine astronomer Carlos Cesco at the Yale-Columbia Southern Station at Leoncito Astronomical Complex in Argentina. It is named after astronomer Gerald Clemence.
1453 Fennia, provisional designation 1938 ED1, is a stony Hungaria asteroid and synchronous binary system from the innermost regions of the asteroid belt, approximately 7 kilometers in diameter. Discovered by Yrjö Väisälä at the Turku Observatory in 1938, the asteroid was later named after the Nordic country of Finland. The system's minor-planet moon was discovered in 2007. It has a derived diameter of 1.95 kilometers and is orbiting its primary every 23.55 hours.
3854 George, provisional designation: 1983 EA, is a stony Hungaria asteroid and Mars-crosser from the innermost regions of the asteroid belt, approximately 3.5 kilometers in diameter. It was discovered on 13 March 1983, by American astronomer couple Carolyn and Eugene Shoemaker at the Palomar Observatory in California. The unlikely synchronous binary system has a rotation period of 3.3 hours. It was named after the discoverer's father-in-law, George Shoemaker.
9069 Hovland, provisional designation 1993 OV, is a stony binary Hungaria asteroid from the inner regions of the asteroid belt, approximately 3 kilometers in diameter.
3353 Jarvis, or by its provisional designation, 1981 YC, is a carbonaceous Hungaria asteroid, slow rotator and suspected tumbler from the inner regions of the asteroid belt, approximately 10 kilometers in diameter.
5899 Jedicke, provisional designation 1986 AH, is a binary Hungaria asteroid approximately 3 kilometers in diameter. It was discovered on 9 January 1986, by American astronomer Carolyn Shoemaker at Palomar Observatory, and named after the members of the Canadian Jedicke family.
5905 Johnson, provisional designation 1989 CJ1, is a Hungaria asteroid and synchronous binary system from the innermost regions of the asteroid belt, approximately 4 kilometers (2.5 miles) in diameter. It was discovered on 11 February 1989, by American astronomer Eleanor Helin at Palomar Observatory in California, United States. Its satellite measures approximately 1.6 km (1 mi) in diameter and orbits its primary every 21.8 hours. It was named after American astronomer and engineer Lindley N. Johnson.
4868 Knushevia, provisional designation 1989 UN2 is a bright Hungaria asteroid and suspected binary system from the innermost regions of the asteroid belt, approximately 2 kilometers in diameter. It was discovered on 27 October 1989, by American astronomer Eleanor Helin at the Palomar Observatory in California, United States. The asteroid was named for the Kyiv University in Ukraine.
2577 Litva, provisional designation 1975 EE3, is a Hungarian-type Mars-crosser and rare trinary asteroid from the inner regions of the asteroid belt, approximately 4 kilometers in diameter.
2074 Shoemaker, provisional designation 1974 UA, is a stony Hungaria asteroid, Mars-crosser and suspected synchronous binary system from the innermost regions of the asteroid belt, approximately 4 kilometers in diameter. It was discovered on 17 October 1974, by astronomer Eleanor Helin at the Palomar Observatory. She named it after American astronomer Eugene Shoemaker.
4440 Tchantchès, provisional designation 1984 YV, is a rather elongated Hungaria asteroid and a possible binary system from the inner regions of the asteroid belt, approximately 3 kilometers in diameter.
5477 Holmes, provisional designation 1989 UH2, is a Hungaria asteroid and binary system from the innermost regions of the asteroid belt, approximately 3 kilometers (2 miles) in diameter. It was discovered on 27 October 1989, by American astronomer Eleanor Helin at the Palomar Observatory in California. The presumed E-type asteroid is likely spherical in shape and has a short rotation period of 2.99 hours. It was named for American amateur astronomer Robert Holmes. The discovery of its 1-kilometer-sized minor-planet moon was announced in November 2005.
8026 Johnmckay, provisional designation 1991 JA1, is a binary Hungaria asteroid and very slow rotator from the inner regions of the asteroid belt, approximately 2 kilometers in diameter. It was discovered on 8 May 1991, by American astronomer Eleanor Helin at the U.S. Palomar Observatory, California, and later named for NASA test pilot John B. McKay.